the elephants are a symbol of the subratans from libya. efficient transport and specialization brought ostia's economy to a high level of complexity, and surely had a profound effect on people's lives and the character of their city. that effect can be easily seen today in a living city, a city like fez, morocco. archaeologists have come to fez because the same high degree of specialization suggested by the ruins of ostia can be seen here in the flesh. the population and density of the old city of fez has remained the same since the 10th century. archaeologist david webster. the old city of fez had about 120,000 people for its total population. this would have been an equivalent of a population density of tens of thousands of people per square mile. now, the only reason why that was possible, especially in a nonindustrial context, was that you had a very effective agricultural environment around fez within, say, 15 or 20 miles radius. but you also had very effective forms of nonhuman transport -- donkeys, camels, horses, mules -- that coul